Supraspinatus and biceps brachii tendinopathy in dogs

Calcifying tendinopathy was seen on radiographic views of the scapulohumeral joint in 12 of 183 (7 per cent) dogs reviewed retrospectively. Calcifying tendinopathy was identified only in large breed dogs, five being labradors. All the affected dogs, except one, were presented for unilateral thoracic limb lameness, which was typically of a chronic and intermittent pattern. Pain on manipulation of the scapulohumeral joint in the lame leg was present in eight of 12 dogs (67 per cent). Calcification of the supraspinatus tendon was seen in eight dogs and calcification of the biceps brachii tendon was seen in the other four dogs. Radiographic changes indicative of biceps brachii tendon avulsion were found in conjunction with calcification of the contralateral biceps brachii tendon in two dogs. Filling defects, indicative of bicipital tenosynovitis, were also seen in positive contrast arthrograms of two dogs with biceps brachii calcification. Of the eight dogs for which radiographic views of both scapulohumeral joints were available, six dogs had bilateral radiographic signs of calcifying tendinopathy. Overall, radiographic signs of calcifying tendinopathy were seen in 18 scapulohumeral joints, but lameness was apparent in only nine limbs, suggesting the lesion may at times be asymptomatic. Further prospective investigation of calcifying tendinopathy is needed to determine why lameness does not always appear to be associated with the presence of the lesion.     

Supraspinatus tendinosis associated with biceps brachii tendon displacement in a dog

A 4-year-old spayed female Australian Cattle Dog (Blue Heeler) was evaluated because of right forelimb lameness of 5 months' duration. Orthopedic evaluation revealed signs of pain localized to the cranial aspects of both shoulder joints. Via magnetic resonance imaging, the mass of the supraspinatus tendon insertion in both shoulder joints was increased, compared with findings in cadavers of clinically normal dogs; additional imaging procedures revealed that, compared with clinically normal tendons, the tendon had increased signal intensity that was consistent with increased fluid content. The increased supraspinatus tendon mass in each shoulder joint was associated with medial displacement of the biceps brachii tendon, which was more severe in the right limb. Arthroscopic evaluations of both shoulder joints revealed no abnormalities. The dog underwent surgery, and the abnormal parts of the tendons were resected. The most prominent finding on histologic examination of excised tissues was severe myxomatous degeneration. The lameness resolved, and at 22 months after surgery, the dog was reported to have had no recurrence of lameness. The clinical signs and histologic appearance of the tendons in this dog strongly resemble findings associated with tendinosis in humans. Decompression of the biceps brachii tendon may have contributed to the successful outcome after surgery in this dog. Supraspinatus tendinosis should be considered among the differential diagnoses in dogs with uni- or bilateral forelimb lameness.     

Standing biceps brachii tenectomy to treat chronic bicipital tendinopathy associated with bursal fibrosis and humeral adhesions in a Quarter Horse gelding

Chronic biceps brachii (BB) tendinopathy is a rare cause of lameness in horses that can be challenging to diagnose and treat successfully. This pathology is typically insidious in onset and unresponsive to conservative treatment. A 12-year-old Quarter Horse gelding presented for chronic severe lameness of the left forelimb that was localised to the left shoulder area. The horse was unresponsive to conservative management and surgical exploration revealed a grossly enlarged proximal BB tendon, a thickened fibrotic bicipital bursa and adhesions between the tendon, humerus and bursa. With standing sedation and local anaesthesia, the adhesions were debrided and 10 cm of the affected tendon was excised. Immediately post-operatively, the left forelimb lameness dramatically decreased. The horse recovered well and after rehabilitation returned to the previous level of athletic performance without evidence of lameness or gait abnormality. In this case, tenectomy of the chronic unresponsive BB tendinopathy, with associated bursal fibrosis and humeral adhesions, was successful and resulted in a return to previous athletic performance without complications. Standing excision of the BB tendon may be a viable treatment option for chronic BB tendinopathy and associated conditions when there is significant compromise to the integrity of the BB tendon.     

Rupture of the biceps brachii tendon sheath in two dogs

Rupture of the biceps brachii tendon sheath was diagnosed in two dogs which were presented with chronic thoracic limb lameness. In each case, diagnosis was achieved by positive contrast arthrography, which revealed obvious leakage of contrast agent from the distal portion of the tendon sheath. Arthroscopy was performed in each affected shoulder joint and no other significant lesions were found. In one dog, concomitant bicipital tendinopathy was confirmed by histopathology. Both dogs were treated by bicipital tendon transposition, and tenodesis and both showed improvement in the degree of lameness following surgery. Tearing of the biceps brachii tendon sheath has not been reported previously but should be included in the differential diagnosis for shoulder lameness in the adult dog.     

Calcifying aponeurotic fibroma on the paw in a dog

A 12-year-old, spayed female, Maltese dog with a round and firm mass on the dorsal part of the left rear paw and a cervical mass was brought to the clinic. The paw mass was contiguous to the adjacent tendon; it was composed of neoplastic mesenchymal cells and had scattered foci of calcification with chondroid differentiation microscopically. The neoplastic cells were positive for vimentin and S100, but negative for desmin and smooth muscle actin. Microscopic features and immunohistochemistry results were consistent with calcifying aponeurotic fibroma (CAF). The cervical mass was composed of polygonal cells forming acini with marked anisocytosis and anisokaryosis and diagnosed as thyroid follicular carcinoma. No recurrence or metastasis occurred during follow-up. To the best of our knowledge, this is the first case of canine CAF with features identical to its human counterparts.Key clinical message:This report describes the rare case of calcifying aponeurotic fibroma on the paw in a dog. This is apparently the first case in the veterinary literature with identical clinical and pathological features to the human counterpart.     

Arthroscopic biceps brachii tenotomy as a treatment for canine bicipital tenosynovitis

Five dogs of varying breeds, ranging from 4 to 8 years in age, were presented with clinical signs consistent with bicipital tenosynovitis. After failure of conservative treatment, each dog underwent shoulder arthroscopy. Following examination of the scapular humeral joint, the bicipital tendon was severed with a bipolar radiofrequency electrosurgical system. The arthroscopic procedure resulted in a good to excellent outcome for all five dogs.     

Medial displacement of the tendon of origin of the biceps brachii muscle in 10 greyhounds

The history, clinical signs and treatment of 10 greyhounds with medial displacement of the tendon of origin of the biceps brachii muscle secondary to rupture of the transverse humeral ligament are described. The aetiology of the condition and the prognosis for return to racing are discussed.     

The location of projection neurons to the biceps brachii muscle in the telencephalon of the pigeon

Few studies regarding the anatomical distribution of motor neurons innervating muscles of the arm have been demonstrated in avian brains. The purpose of this study was to finely determine the localization of cerebral neurons innervating the biceps brachii muscle in the pigeon. The cholera toxin B subunit (CTB) was employed as a retrograde tracer to determine the location of neurons controlling the biceps brachii muscle in the telencephalon following intramuscular injection in male pigeons (n = 7), which were killed 14 days after intramuscular injection with CTB. We found that CTB‐labelled neurons were located contralaterally in the hyperpallium apicale of the rostral telencephalon and that most of the CTB‐labelled neurons were pyramidal in shape. This study shows that CTB is easily taken up by nerve terminals which innervate the biceps brachii muscle of the pigeon and that cerebral motor neurons controlling the biceps brachii muscle are located in the hyperpallium apicale.     

Ultrasonographic examination of the proximal tendon of the biceps brachii: Technique and reference images

Ultrasonography of the shoulder is of interest in the diagnosis of proximal forelimb lameness. The proximal tendon of the biceps brachii (PTBB) and its associated structures are frequently injured and should be included in the routine ultrasonographic examination of the shoulder. This paper describes a complete ultrasonographic procedure for examining the bicipital apparatus, on transverse and longitudinal scans, from the insertion of the PTBB on the supraglenoid tubercle to the muscle body below the intertubercular sulcus.     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.     

Complete biceps brachii tenotomy to facilitate internal fixation of supraglenoid tubercle fractures in three horses

OBJECTIVE: To describe a method for internal fixation of supraglenoid tubercle fractures in conjunction with complete tenotomy of the biceps brachii tendon. ANIMALS: Three horses, ranging in age from 8 months to 2 years and weighing from 300 to 400 kg. METHODS: Fractures were repaired by open reduction-internal fixation using bone screws placed in lag fashion and complete tenotomy of the biceps brachii tendon. OUTCOME: All three horses were sound for their intended use with a good cosmetic result 6 months after surgery. CONCLUSIONS: Complete transection of the biceps brachii tendon facilitates supraglenoid tubercle fracture repair by reducing tensile forces exerted on the supraglenoid tubercle. Complete tenotomy does not appear to preclude return to a successful athletic career.     

Ultrasonography for the diagnosis of diseases of the tendon and tendon sheath of the biceps brachii muscle

OBJECTIVE: To describe the ultrasonographic appearance of the normal and diseased biceps brachii tendon and its tendon sheath in dogs. STUDY DESIGN: A prospective clinical study. ANIMALS: One hundred twenty client-owned dogs. METHODS: In the first part of the study, the ultrasonographic appearance of the normal biceps brachii muscle and the surrounding soft tissue was determined in 27 healthy dogs. Standard views were described and established. In the second part, 120 dogs with suspected pathology of the biceps brachii muscle were examined ultrasonographically. Fifty-five of these dogs had no sonographic changes, and 65 dogs had sonographically detectable pathologic changes of the tendon or the tendon sheath or both. The mean age of the affected dogs was 3.7 years. The ratio of males to females was 1.95:1. Sedation or anesthesia of the dogs was required because of the extreme movements of the leg necessary for the examination. To achieve a perpendicular view of the tendon and the tendon sheath, the area of the shoulder joint was rotated outward and abducted as far as possible. Examination of the muscle-tendon apparatus of the biceps brachii muscle was divided into 4 main sections. RESULTS: Linear transducers (7.5-10 MHz) allowed the soft tissue structures to be easily visualized with ultrasonography. Pathologic changes of the tendon and tendon sheath were visualized sonographically by using high-frequency linear probes. Partial or complete tendon rupture, medial luxation of the tendon, corpora libera in the tendon sheath, and tenosynovitis were clearly shown. CONCLUSIONS: High-frequency ultrasonography using linear transducers allows the examiner to accurately define the pathologic changes in the region of the biceps brachii tendon in dogs. CLINICAL RELEVANCE: The use of sonography for diagnosis of disease processes of the tendon and tendon sheath of the biceps brachii muscle complements clinical and radiographic examination findings.     

Computed tomographic morphometry of the biceps brachii muscle tendon of dogs affected by the medial coronoid disease

The objective of this study was to measure the biceps brachii muscle (BBM) attachment to the medial coronoid process (MCP) using computed tomography images and to compare these data between clinically healthy and dogs affected by medial coronoid disease (MCD). Computed tomography was performed in MCD-affected and healthy dogs. Multiplanar reconstruction views were obtained to measure distance (cm) of the BBM attachment point to the MCP. Results showed that the mean BBM attachment point-to-MCP was 1.42 ± 0.23 cm in MCD-affected and 1.27 ± 0.20 cm in healthy dogs, respectively. In dogs with MCD, the BBM attachment point-to-MCP was significantly more abaxial than in clinically healthy dogs (p < .001). The results of this study support the hypothesis that the BBM attachment site is more abaxial to the MCP and therefore may contribute to supraphysiological overload leading to MCD. Albeit more research is necessary, this study proves a relationship between the BBM attachment point and the development of MCD.     

Variation of fiber types in the triceps brachii, longissimus dorsi, gluteus medius, and biceps femoris of horses

The distribution of type-I and type-II fibers in 9 different parts of the musculi triceps brachii, longissimus dorsi, gluteus medius, and biceps femoris was studied to determine whether biopsies from these muscles give reliable information. All 4 investigated muscles were not homogeneous in their fiber-type distribution. Large differences existed among different muscle parts. The percentage of type-I fibers increased toward the deeper and cranial parts of the muscles. In the same zone of the gluteus muscle, differences of 30% were found for type-I fibers. Therefore, results obtained by biopsies of muscles must be interpreted with caution.     

Die laterokranialen Faszienstrukturen am Ober- und Unterarm sowie Unterschiede im Ansatz des M. biceps brachii bei Haussäugetieren

Structures of the laterocranial Fascia in the Upper- and Forearms of Domestic Mammals, including Differences in the Aponeuroses of the M. biceps brachii The laterocranial fascia of the upper arm and forearm, as well as aponeurotic relationships of the Musculus biceps brachii were investigated on each of ten forelimbs from horses, cattle and swine. Ten canine biceps were also investigated. Equine and bovine fascia contain elastic components. An as-yet undescribed ligament-like aponeuroses of the laterocranial forearm fascia to the Fossa radialis humeri was seen in all three species studied. The laterocraniale fascia of the upper and forearm form a common passage for the Musculi hrachialis et extensor carpi radialis. In the case of the horse, the ulnar aponeurotic tendon of the biceps muscle crosses below the Ligamentum collaterale cubiti medialis. In cattle, on the other hand, it runs between the two branches of the collateral ligament, to attach on the olecranon. This portion of the equine tendon protrudes into the joint. It has connective tissue character in young animals, but becomes fibrocartilaginous in older horses. The radial aponeuroses of the canine biceps exhibits two branches. A situation similar to that seen for the ulnar aponeuroses of the equine Musculus biceps brachii is observed on the inside surface of the porcine Ligamentum cubiti mediate, in which a wedge of connective tissue protrudes into the joint, taking on fibrocartilaginous character in older animals.